Material handling apparatus



Sept. 14, 1965 L. E. MYLTING MATERIAL HANDLING APPARATUS 6 1 9 W .h M f /0 8 NY M w w WM 6 A .v. m mw Z 7 sn 4 M Z MM Y B Filed April 9, 1962 sept- 1965 L. E. MYLTING 3,206,254

MATERIAL HANDLING APPARATUS Filed April 9, 1962 4 Sheets-Sheet 2 I N VEN TOR.

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MATERIAL HANDLING APPARATUS Filed April 9, 1962 4 Sheets-Sheet 3 p 1965 1.. E. MYLTING 3,206,254

MATERIAL HANDLING APPARATUS 4 Sheets-Sheet 4 Filed April 9, 1962 INVENTOR.

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United States Patent 3,206,254 MATERIAL HANDLING APPARATUS Lauritz E. Mylting, Ardmore, Pa., assignor, by mesne assignments, to Buell Engineering Company, Inc, Lehanon, Pa., a corporation of Delaware Filed Apr. 9, 1962, Ser. No. 186,251 3 Claims. (Cl. 302-49) This invention relates generally to material handling apparatus, and more specifically to rotary feeders for feeding divided solid materials.

In recent years, there has been a need for feeding apparatus capable of efiiciently handling granular solid materials having a particle size up to inch in a manner which facilitates the transporting of such materials from bins and hoppers. For example, in the iron and steel industry, it is necessary to charge materials, such as ore, limestone, lime, scale and the like, into blast furnaces and open hearths. The improvements that have been made in steel and iron making techniques, such as the socalled oxygen process, have demanded new systems of charging the materials into the melting furnaces and more eificient feeding apparatus for use in such systems than have been available in the past.

Further, for many years, there has been a need for apparatus useful in charging solids, such as lining material, into a furnace to replace the materials removed during a heat. For example, in patching the front, back and bottom walls of an open hearth, it has been the conventional practice manually to shovel or mechanically sling the lining materials through the open door of the furnace. Often the lining material would be wasted since it could not be thrown far enough and accurately enough to reach the portions of the Walls requiring repair, or to be im pinged on the walls with enough force.

The method of my copending application Serial No. 195,725, filed May 18, 1962, describes and claims a system for charging divided or granular materials, such as .ore, limestone, lime, scale, and the like, as well as lining materials, into a melting furnace. In one embodiment, that system contemplates feeding the granular solids from hoppers under approximately atmospheric pressure into streams of swiftly moving air at pressures higher than atmospheric pressure so that the solids can be transported and charged into an oxygen or open hearth furnace directly onto the melt. Among the advantages which are obtained with the system are the successful adaptation of the oxygen process to the conventional open hearth and a speeding up of the metallurgical reactions. The system also is useful in charging lining materials into a furnace.

Although not limited thereto, the present invention aims to provide rotary feeder apparatus capable of being embodied in the charging system described in my above-identified copending application. More particularly, it is a purpose of the present invention to provide rotary feeder apparatus for continuously transferring granular solids from a hopper at atmospheric pressure to a stream of gas flowing at high speed under a pressure greater than atmospheric pressure.

It is recognized that rotary feeders have been used heretofore. However, when it was attempted to use these conventional rotary feeders to remove solids from a hopper and deliver them to a swiftly moving stream of pressurized air, it was found that the feeders were subject to such dimculties as air binding wherein slow or non-uniform feeding of the solids resulted by reason of the high pressure existing the chamber into which the solids are transferred from the hopper. Further, the volumetric efficiency of conventional rotary feeders varies widely with differences in the gas pressure, which, for example, may vary from O to pounds per square inch gauge.

3,206,254 Patented Sept. 14, 1965 Conventional feeding apparatus also has been found not to be satisfactory when efforts were made to use them for feeding certain solids, as, for example, Lac Jeannine ores. These ores readily form dense layers whensubjected to air under higher than atmospheric pressure and these dense layers soon become substantially impervious to gas flow therethrough. When such a layer is formed in the hopper of a feeder, the rate of feeding varies widely, as does the quantity of solids in successive feedings.

Another consideration which has become extremely important with my new solids injection system is that the rotary feeders which are required must be capable of being adjusted and maintained by semi-skilled labor. As would be expected, the feeders are subject to wear during an open hearth campaign and may require replacement of parts. Since the rotary feeders of the invention are particularly adapted for use in a system which materially reduces the time for an open hearth heat, the time available for such maintenance has been reduced in proportion. For example, a normal maintenance job on a rotary feeder should not require over one hour. This problem of maintenance further is complicated by the fact that the help available in an open hearth plant usually is not skilled for such repair.

The present invention satisfies all of the considerations discussed above and overcomes the disadvantages associated with prior art rotary feeding devices. In its preferred construction, the invention generally contemplates the provision of a rotor having a plurality of pocket-like chamhers for receiving solids from a hopper and delivering the solids into a swiftly moving stream of air. Provision is made successively to reduce the air ressure in each rotor pocket to approximately atmospheric pressure as the pockets are moved to the mouth or outlet Zone of the hopper to receive the solids. The apparatus further includes means for releasing the air from the pockets that is displaced by the solids discharged from the hopper. In this manner, at most only a brief contact of air under pressure with the lower surface of the solids in the hopper results. Since the air in the pockets is at about the same pressure as the ressure in the hopper, there is no substantial penetration of the air into the solids and, hence, a gas impervious bed is prevented from developing in the solids. Further, even if such air-ore contact initiated a slight for mation of a crust or air impervious bed, the bed is removed when the next successive pocket of the rotor is filled.

The invention is particularly valuable since it does not require that the solids should be reduced to a small size, for example, granules less than "4 inch. Further, it is capable of feeding not only ore which cannot be readily pelletized or sinterecl and ore which is highly abrasive, but also mill scale, fines from sintering machines, and other fine ores and metal values which generally are considered a nuisance in a steel plant.

Problems of maintenance have been successfully overcome by a novel construction which permits the several component parts to be easily replaced without completely dismantling and/ or removing the entire feeder. To this end, the rotary feeder of the invention preferably is constructed so that both supporting bearings for the rotor shaft are located externally md at one side of the feeder housing. The other side of the housing has a removable plate, which may be a hinged door. This construction permits the rotor to be pulled from its shaft and readily removed through the open door of the housing. The shoe which normally is provided in the housing can be removed easily in the same manner. Addition-a1 means are provided for permitting the rotor shaft and its supporting hearings to be disconnected from the feeder as a unit.

As will be apparent from the foregoing description, the arrangement provided by the invention permits all of the wear parts to be readily extracted from the rotary feeder and to be individually replaced as units. Assembly of the several units that form the feeder is very simple and can be easily accomplished in a machine shop or the like instead of in the cramped and unfavorable conditions of an open hearth shop.

The present invention will be better understood by those skilled in the art from the following specifications and the drawings, in which:

FIGURE 1 is a schematic showing of a solids injection system embodying the present apparatus;

FIGURE 2 is a vertical, transverse sectional view showing one form of the solids feeders contemplated by this invention;

FIGURE 3 is a sectional View taken on the line 3-3 of FIG. 2;

FIGURE 4 is a sectional view taken on the line 4-4 of FIG. 2;

FIGURE 5 is a View similar to FIG. 4, but of a slightly modified feeder construction;

FIGURE 6 is a vertical, transverse, sectional view showing still another embodiment of the invention;

FIGURE 7 is an end view, with a portion of the cover plate broken away, of the embodiment illustrated in FIG. 6;

FIGURE 8 is a sectional view taken on the line 88 of FIG. 6; and,

FIGURE 9 is a top plan View of the embodiment illustrated in FIG. 6.

Reference is finst made to FIG. 1 which, as noted above, schematically illustrates an exemplary embodiment of the invention in the solids injection system described in my copending application, Serial No. 195,725. It is to be understood that the invention is not limited to use in such a system and that is has been illustrated only for the purpose of clearly describing the operation of the apparatus, as well as the many advantages that may be provided in this and other applications.

As shown in FIG. 1, a conventional blower 1 is connected to one end of a conduit 2 which extends to an open hearth 3 and projects down through the roof 4 of the furnace. The conduit 2 terminates a short distance below the inner surface of the roof and well above the slag layer 5 which is on top of the molten metal 6. Preferably, two conduits 2 are used with a conventional open hearth furnace with each conduit projecting through the roof at a distance from the adjacent end of the furnace which is approximately equal to one-quarter of the inside length of the furnace. Ox gen lances 7 extends through the roof 4 adjacent to the conduits 2. When high velocity oxygen passes through the lances, the slag will be blown away from the vicinity of the oxygen stream, as generally designated by reference numeral 8, with resultant exposure of a substantially slag-free surface of the molten metal. The solids are discharged onto this slag-free area of the molten metal.

Each conduit 2 has at least one hopper 10 associated therewith, and preferably has as many hoppers 10 as there are different kinds of solids to be conducted to the furnace, although one hopper may serve to feed several solids, one at a time, or even more than two mixed solids, if this is desired. Each hopper 10 is provided with a solids feeder which is connected to the conduit 2. One preferred construction of this feeder is illustrated most clearly in FIGS. 2, 3 and 4.

As shown in FIGS. 2, 3 and 4, the hopper 10 has a bottom discharge opening 11. The feeder itself consists of a spool piece 15, a housing 16, a rotor 17 within the hous ing, and a pipe 18 which connects the housing 16 to the conduit 2. The feeder carries a motor 19 (see FIG. 1) which serves to drive the rotor 17 of the feeder through a chain 20 and a gear 21.

The spool piece 15 is short in vertical length and is provided with horizontally extending top flanges 21 and bottom flanges 22. The top flanges may be attached, as with bolts (not shown), to the corresponding flanges 23 at the bottom of the hopper 10. The bottom flanges 22 of the spool piece are of a size to rest on the top edges of the housing 16 to which they may be attached, as by cap screws 24. The spool piece 15 is provided with a recess 25 from which an exhaust pipe 26 leads, and has a passage 27 which forms a continuation of the passage 11 in the hopper 10 and through which solids may flow from the hopper to the rotor.

Within the housing 16 and suspended from the flanges 22 of the spool piece 15, as by cap screws 29, is a shoe 30, which is provided with a central flow passage 31 in communication with the passage 27 of the spool piece. At its lower end, the shoe is provided with two longitudinal, diverging extensions 33. The lower surfaces of the shoes and its extensions are curved on an are so as to have close fitting engagement with the outer periphery of the rotor; that is, the clearance between the rotor and the shoe is so small that only unconsequential quantities of air may flow therebetween. The shoe 30 further is provided with an annular passage 35 which extends around the passage 31. This passage 35 opens through the bottom arcuate surfaces of the shoe and its extensions 33. At its upper end, the passage 35 is in communication with the passage 25 in the spool piece 15. It will be understood that air under pressure which passes into the passage 35 and will enter the lower end of the passage 25 and then escape to the atmosphere through the exhaust pipe 26.

The housing 16 includes end walls and side walls 41, the latter being shaped to conform generally to the cylindrical shape of the rotor 17. In the illustrated embodiment of FIGS. 2, 3 and 4, a shaft 42 extends through the end walls 40 and is supported in bearings 43 secured to the outer sides of the end wall 40. Stuffing boxes 44 preferably are employed to prevent the escape of fine solids from within the housing along the shaft and into the bearings. The gear 21 is keyed to one end of the shaft 42.

The rotor 17 includes a hub which surrounds and has a driving connection with the shaft 42. The rotor has two disc-shaped ends 51 that are provided with flanges 52 and has a plurality of Walls 54 which extend lengthwise of the hub 50 between the end walls 51. Each adjacent pair of walls 54 partially defines a pocket 55 for receiving solids discharged through the passage 31. The outer peripheries of the flanges 52 and the walls 54 make close fitting engagement with the lower surface of the shoe 30 and its extensions 33.

It will be noted that the outer edges 56 of each of the walls 54 are widened in circumferential directions so that each edge will span and close the open end of the passage 35; and that the circumferential distance between adjacent walls 54 is less than the corresponding length of each extension 33.

In operation of the embodiment illustrated in FIGS. 2, 3 and 4, let it be assumed that the conduit 2 is a pipe five inches in diameter, that the blower 1 is capable of delivering approximately 1200 cubic feet of air per minute into that pipe at 11 to 12 pounds per square inch gauge with a resulting velocity of about 4800 feet per minute, and that the passage 11 from the hopper 10 is about 8 inches square with the pipe 18 being about 3 inches in diameter. When the feeding operation is initiated, the velocity of the air stream is about feet per second, but, as the feeding continues, this velocity may, and usually does, increase to as much as feet per second when the last of the solids are being discharged from the hopper 10.

Let it also be assumed that the hopper 10 contains a quanity of iron ore, as for example, Lac Jeannine ore, and that the particles of such ore range in size from about one-half inch maximum to about 100 mesh or even smaller. As discussed above, this particular ore cannot be air fluidized and forms a surface crust or layer which is substantially impervious to the flow of gas therethrough when it is subjected to air at a pressure higher than atmospheric pressures. When the blower 1 is discharging air into the conduit 2, as described above, the air pressure within the housing 16 will be substantially the same as that in the conduit 2, that is, considerably above the atmospheric pressure existing in the hopper 1G.

The rotor 17 is actuated by the motor 19 at such a rate that the' ore will be fed into the conduit 2 in quantities slightly less than the solids carrying capacity of the air stream. As the rotor rotates counterclockwise, as viewed in FIG. 2, one pocket 55 after another traps air under the higher pressure within the housing 16 when that pocket is closed by the right hand shoe extension 33. As the rotor continues to rotate, the edge of the leading wall 54 of t e pocket uncovers the lower opening of the recess 35, whenupon the high pressure air in the pocket escapes through the passages 35, 25 and from the pipe 26 to the atmosphere. While the high air pressure gas is thus escaping, the same leading edge is maintaining close fitting contact with the shoe 3% so as to prevent flow of the high pressure air from the pocket into the passage 31 and into contact with the ore therein. Hence, there is substantially no tendency for the ore particles in the shoe and/ or spool to form a gas impervious bed due to contact with the high pressure air. On the contrary, little or no impedance is offered to the flow of Solids into the pockets 55 as the rotor moves them beneath the passage 31.

Each pocket 55 contains air at approximately atmospheric pressure when the pocket communicates with the passage 31 and is in position to receive solids discharging through the passage. This air-ore contact is only momen tary, however, and does not tend materially to impede the flow of ore through the passage 31, since, when the leading wall 54 of the pocket 55 uncovers the passage 35 in the other extension 33, any air in the pocket will be displaced by the ore falling thereinto and will escape through passages 35, 25 and the exhaust pipe 26. Further, the brief contact of air under atmospheric pressure with the lower surface of the solids in the passage 31 does not result in any substantial penetration of the air into the body of the solids in the passage 31 and has little or no effect in inducing the formation of a gas impervious bed in the solids.

Even if the air-ore contact might initiate the formation of such a crust at the lower surface of the ore in the passage 31, such a bed would be removed when the next pocket is filled and a fresh layer of solids will be presented to the next pocket, that is, a layer which has not been made non-flowable.

Reference is next made to FIG. 5, which partially illustrates an apparatus that is quite similar in its genera construction and manner of operation to the embodiment discussed above in connection with FIGS. 2, 3 and 4. In FIG. 5, however, the air passage in the shoe which surrounds the central solids flow passage is divided into four separate passages 61). Each of these passages 61 cornmunicates with an air recess 61 formed in the spool piece 62 around its central passage (not shown). Outlet pipes 63 connect the several recesses 61 to the atmosphere.

In FIGS. 6, 7, 8 and 9 there is illustrated the rotary feeder apparatus of the invention which is considerably easier to adjust and maintain than rotary feeder constructions of the prior art. This improved rotary feeder con struction is shown to consist generally of a spool piece 115, a housing 116, and a rotor 117 within the housing.

The spool 115, which may be the same as that discussed in connection with either FIGS. 2, 3 and 4, or with FIG. 5, is provided with horizontally extending top flanges 121 and bottom flanges 122. As in the case of the previously described spool pieces, the top flanges 121 may be attached to the corresponding flanges of a hopper (not shown). The bottom flanges of the spool piece rest on the top edges of the housing 116 and are attached thereto, as by cap screws 124. The spool piece 115 has one or more air recesses 125 connected by a corresponding number of exhaust pipes 126 to the atmosphere and is provided with a solids flow passage 127 which may be aligned with the passage of the hopper and through which the solids may flow from the hopper to the rotor.

A shoe 139 having a central solids flow passage 131 which communicates with the passage of the spool piece 115 is disposed within the housing 116 and is suspended from the flanges 121 of the spool piece, as by cap screws At its lower end, the shoe is provided with two longitudinal, diverging extensions 133. The lower surfaces of the shoe and its extensions are curved on an are so as to have a close-fitting engagement with the outer periphery of the rotor 117, which is similar in construction to the previously described rotor 17. The shoe is provided with a passage 135 which may correspond to the annular passage 35 illustrated in FIG. 4 or to the several passages 60 illustrated in FIG. 5.

According to this embodiment of the invent-ion, the housing 116 includes curved side walls that generally conform to the cylindrical shape of the rotor 117, a fixed end wall :141 having a central opening 142, and an opposite end wall which is formed by a removable cover plate 143. The cover plate 143 preferably is hinged at one side, as generally designated by reference numeral 144, so that it can be swung open to expose the rotor 117 and the shoe 130 for easy replacement. As shown, the cover 143 is provided with threaded studs 145 having external handles 146 which permit the cover plate to be tightly clamped to the housing when the feeder is in operation. A sealing ring 147 is provided on the inner face of the cover 143 to prevent the escape of high pressure air from within the housing.

The hub of the rotor 117 surrounds and has a driving connection on one end portion of the shaft 156. In the illustrated embodiment, this driving connection is formed by a drive plate 157 at the end of the housing adjacent the cover plate 143. The drive plate 157 is secured to the end face of the rotor and to the corresponding end of the shaft 156, as by bolts 158 and 159, respectively. The opposite end of the rotor has a flange extension 161) which surrounds the shaft 156.

The shaft 156 extends through the opening 142 of the end wall 141 and is supported exteriorly of the housing by bearings 165. These bearings are carried within a shaft housing 166 which is attached to the housing 116 of the feeder. The shaft housing includes vertically extending side legs 167 which are formed with guide lips 16% that are slidably engageable with grooves 169 (FIG. 9) formed in opposite side edges of the end wall 141. The shaft housing 166 may be vertically adjusted along the end wall of the feeder housing by adjusting bolts 170 which are carried at the bottom of the feeder housing 116 and engage the bottom of the shaft housing. By adjusting these bolts, it is possible to vertically position the rotor shaft so that the periphery of the rotor is disposed in close-fitting engagement with the lower surface of the shoe 130 and its extensions 133. The shaft housing 166 may be secured in its adjusted position by any suitable means, as by bolts 171, which are threaded through the legs 16'! into engagement with the end wall 141 of the feeder housing.

The opening 142 in the end wall 141 of the feeder housing is closed by an annular plate .176 that is disposed within the housing 116 and by an external clamping plate 177. The two plates are secured together, as by cap screws 173, so as to respectively engage the inner and outer surfaces of the end wall 141 around its opening.

7 The plates may be provided with O-rings 179 so that the fluid-tight seal is formed with the end wall. As shown, the plate 176 further is provided around its radially inner edge with spaced packing glands 131) which engage the flange extension 160 of the rotor, and with a lantern ring 181 between the packing glands. The end wall 141 is formed with one or more fluid passages 18?. that open into an annular fluid chamber 183 around the radially inner edge of the end Wall. This annular air chamber 183 is connected by passages 184 to the lantern ring. During operation of the feeder apparatus, air or an inert gas is supplied to the lantern ring at approximately one pound greater pressure than the internal feeder pressure within the housing 116. This flow of air or inert gas passes from the lantern ring into the interior 'of the feeder housing and effectively prevents grit from escaping from the housing into the bearings 165.

A worm gear 1% is keyed to the rotor shaft 156 within the shaft housing and meshes with a worm 191 on a vertical shaft 192 that is supported by bearings 193. The upper end of the worm shaft 192 extends from the housing 166 and carries a pulley 194 which is connected by a suitable belt 1% to a pulley 196 on the shaft of a motor 197. This motor 197 is connected to the feeder housing by a bracket 198 so that it can be replaced easily.

The operation of the apparatus of FIGS. 6, 7, 8 and 9 is generally similar to that discussed above in conjunction with the apparatus illustrated in FIGS. 2, 3 and 4. When the motor 197 is energized the rotor shaft 166 will be rotated so as to move the rotor 117 in a counterclockwise direction, as viewed in FIG. 7. This causes the pockets 155 of the rotor to be successively closed by the right hand shoe extension 133 so that the trapped air in the pockets is reduced to atmospheric pressure. Thereafter, the rotor pockets are moved into communication with the passage 131 of the shoe to receive the solids from the hopper. The solids in the rotor pockets then are delivered into the switftly moving stream of air in the conduit (not shown) to which the lower end of the feeder housing is connected.

Although the last described embodiment of the invention has been described as including means for reducing the pressure of the air initially trapped in the rotor pockets to atmospheric pressure and then permitting the air displaced from the pockets by the solids to be exhausted, it will be apparent that such means could be eliminated, if desired. In such an instance, the illustrated spool piece and shoe could be replaced by a spool piece and shoe of conventional construction. The unitized construction of the feeder apparatus still would provide many advantages in the way of improved maintenance over prior art rotary feeders.

During an open hearth campaign, the parts that are primarily subjected to wear in the rotary feeder are the rotor, the shoe, and the packing glands. With the abovedescribed feeder construction, all of these parts can be replaced readily without removing the entire feeder from the system. For example, the rotor and the shoe can be replaced by opening the hinged door or cover plate 143 to expose the interior of the feeder housing. Thereupon, the drive plate 157 may be disconnected from the rotor and the end or" the shaft so that the rotor can be slid from the shaft and taken from the housing. By releasing the cap screws 129, the shoe 130 can be disconnected from the spool piece 115 and also easily removed from the feeder housing. The plate 176 which carries the packing glands and the lantern ring can be removed from the feeder housing by disconnecting the clamping plate 177. This permits the packing rings and lantern ring to be replaced and assembled in a machine shop or the like instead of under the cramped and unfavorable conditions in the open hearth shop.

Further, the shaft 156 and the shaft housing 166 can be removed as a unit from the feeder by detaching the rotor and in the manner described above and then disengaging the legs 167 from the end wall 141. This, of course, facilitates the repair of any internal parts within the shaft housing, as for example, the worm shaft, the worm gear, and the bearings. When the desired repairs have been made, the shaft housing can be reassembled by simply engaging the lips of the legs within the grooves of the end wall and adjusting the screws 170 until the outer periphery of the rotor is in close fitting engagement with the shoe and its extensions.

Thus, it will be apparent from the foregoing that all of the repair normally encountered with rotary feeders can be accomplished with a minimum of down-time. Further, the repairs can be made by the people most skilled for the purpose and can be done in more favorable conditions than in an open hearth shop. One point of particular importance which should be noted is that the several parts that are most subject to wear can be replaced as units. Thus, the time required for repair is only that which is necessary to remove the required parts from the feeder in the manner described above and then replace the parts with substitute parts.

Having thus described this invention in such full, clear, concise and exact terms as to enable any persons skilled in the art to which it pertains to make and use the same, and having set forth the best mode contemplated of carrying out this invention, I state that the subject matter which I regard as being my invention is particularly pointed out and distinctly claimed in the appended claims, it being understood that equivalents or modifications of, or substitutions for, parts of the above specifically described embodiments of my invention may be made without departing from the scope of the invention as hereinafter defined.

What is claimed is:

1. A rotary feeder for granular solids comprising a rotor housing, said housing including a fixed end wall and a removable end wall, a shoe in the upper part of said rotor housing having a central passage for permitting the flow of solids into said rotor housing, rotor means disposed within said rotor housing in close fitting peripheral engagement with the lower surface of said shoe, said rotor means having a plurality of pockets for receiving solids from the central passage of said shoe and discharging the solids from the outlet opening of said rotor housing, a rotor shaft connected to said rotor and having one end spaced from and disposed inwardly of said removable end wall and the other end extending from said rotor housing through said fixed end wall, a shaft housing substantially enclosing the extending end of said shaft, means detachably connecting said shaft housing to said feeder housing, spaced-apart bearing means carried by said shaft housing for supporting said shaft, said connecting means including means for vertical- 1y adjusting said shaft housing relative to said rotor housing, whereby said rotor means can be moved toward and Way from the lower surface of said shoe, and motor drive means carried by said feeder for rotating said shaft and operatively coupled to the shaft intermediate said spaced-apart bearings.

2. A rotary feeder as claimed in claim 1 wherein said shaft is drivingly connected to said rotor means by a drive plate, said drive plate being removably secured to one end of said shaft and to the corresponding end face of said rotor means.

3. A rotary feeder for granular solids comprising a rotor housing having an inlet opening at its upper end and an outlet opening at its lower end, said rotor housing including a fixed end wall and a removable end Wall, a shoe removably mounted in the upper part of said rotor housing and having a passage therein for permitting solids to flow therethrough from said housing inlet opening into said rotor housing, rotor means disposed within said rotor housing in close fitting peripheral engagement with the lower surface of said shoe, said rotor means having a plurality of pockets for receiving solids from the passage in the shoe and discharging the solids into said housing outlet opening, a rotor shaft carrying said rotor means and having one end spaced from and disposed inwardly of said removable end wall and the other end extending from said rotor housing through said fixed end Wall, sealing means between said shaft and said fixed end wall for preventing material from passing outwardly from Within said rotor housing, a shaft housing including bracket means and a body portion carried by said bracket means and surrounding said extending end of said shaft, first bearing means carried by said shaft housing near said bracket means and second bearing means carried by said shaft housing near the outermost end thereof for rotatably supporting said shaft, means detachably connecting said shaft housing bracket means to said rotor housing fixed end Wall, means engaging said bracket means for adjusting said shaft housing relative to said rotor housing such that the said rotor means is movable toward and away from the lower surface of said shoe, and motor drive means carried by said feeder for rotating said shaft operatively coupled to said shaft intermediate said first and second bearing means.

References Cited by the Examiner UNITED STATES PATENTS 585,804 7/97 Weber 30249 967,075 8/10 Sparrow 30249 1,321,262 11/19 Townsand 30249 1,823,905 9/31 Kreutzberg 302-49 1,900,458 3/ 33 Morrow 302-49 2,75 0,23 3 6/56 Yellott 3 02-49 2,858,212 10/58 Durant 302-49 2,877,057 3/59 Buman 30249 2,888,175 5/59 Harrison 222368 3,058,780 10/62 Swanson 302-49 3,130,879 4/64 Messing 222-368 FOREIGN PATENTS 837,854 11/38 France.

597,492 5/ 34 Germany.

764,411 12/56 Great Britain.

OTHER REFERENCES Brieden: German application Serial No. M 19,015, printed JanuarylZ, 1965 (K15 d 14).

SAMUEL F. COLEMAN, Primary Examiner.

ANDRES H. NIELSEN, Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Nor 3,206,254 September 14, 1965 Lauritz E. Mylting error appears in the above numbered pat- It is hereby certified that t the said Letters Patent should read as ent requiring correction and the corrected below.

- away column 10,

Signed and sealed this 24th day of May 1966,

(SEAL) Attest:

ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNER Commissioner of Patents 

1. A ROTARY FEEDER FOR GRANULAR SOLIDS COMPRISING A ROTOR HOUSING, SAID HOUSING INCLUDING A FIXED END WALL AND A REMOVABLE END WALL, A SHOE IN THE UPPER PART OF SAID ROTOR HOUSING HAVING A CENTRAL PASSAGE FOR PERMITTING THE FLOW OF SOLIDS INTO SAID ROTOR HOUSING, ROTOR MEANS DISPOSED WITHIN SAID ROTOR HOUSING IN CLOSE FITTING PERIPHERAL ENGAGEMENT WITH THE LOWER SURFACE OF SAID SHOE, SAID ROTOR MEANS HAVING A PLURALITY OF PPCKETS FOR RECEIVING SOLIDS FROM THE CENTRAL PASSAGE OF SAID SHOE AND DISCHARGING THE SOLIDS FROM THE OUTLET OPENING OF SAID ROTOR HOUSING, A ROTOR SHAFT CONNECTED TO SAID ROTOR AND HAVING ONE END SPACED FROM AND DISPOSED INWARDLY OF SAID REMOVABLE END WALL AND THE OTHER END EXTENDING FROM SAID ROTOR HOUSING THROUGH SAID FIXED END WALL, A SHAFT HOUSING SUBSTANTIALLY ENCLOSING THE EXTENDING END OF SAID SHAFT, MEANS DETACHABLY CONNECTING SAID SHAFT HOUSING TO SAID FEEDER HOUSING, SPACED-APART BEARING MEANS CARRIED BY SAID SHAFT HOUSING FOR SUPPORTING SAID SHAFT, SAID CONNECTING MEANS INCLUDING MDANS FOR VERTICALLY ADJUSTING SAID SHAFT HOUSING RELATIVE TO SAID ROTOR HOUSING, WHEREBY SAID ROTOR MEANS CAN BE MOVED TOWARD AND WAY FROM THE LOWER SURFACE OF SAID SHOE, AND MOTOR DRIVE MEANS CARRIED BY SAID FEEDER FOR ROTATING SAID SHAFT AND OPERATIVELY COUPLED TO THE SHAFT INTERMEDIATE SAID SPACED-APART BEARINGS. 